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A DAY IN THE LIFE OF A TURD W hen I was a kid, I listened to army veterans talk- ing about their stints in the Korean War. Usually after a beer or two, they’d turn their conversation to the “outhouses” used by the Koreans. They were amazed, even mystified, about the fact that the Koreans tried to lure passersby into their outhouses by making the toilets especially attractive. The idea of someone wanting someone else’s crap always brought out a loud laugh from the vets. Perhaps this attitude sums up the attitudes of Americans. Humanure is a waste product that we have to get rid of, and that’s all there is to it. Only fools would think otherwise. One of the effects of this sort of attitude is that Americans don’t know and probably don’t care where their humanure goes after it emerges from their rear ends as long as they don’t have to deal with it. MEXICAN BIOLOGICAL DIGESTER Well, where it goes depends on the type of “waste disposal sys- tem” used. Let’s start with the simplest: the Mexican biological digester, also known as the stray dog. In India, this may be known as the family pig. I spent a few months in southern Mexico in the late 1970s in Quintana Roo on the Yucatan peninsula. There, toilets were not available; people simply used the sand dunes along the coast. No problem, though. One of the small, unkempt and ubiquitous Mexican dogs would wait nearby with watering mouth until you did your The Humanure Handbook — Chapter 5: A Day in the Life of a Turd 83 Chapter_5:Layout 1 7/27/2011 8:52 PM Page 83

Transcript of A DAY IN THE LIFE OF A TURD W - jenkinspublishing.com chapters/Chapter_05.pdf · A DAY IN THE LIFE...

A DAY IN THE LIFE OF A TURD

When I was a kid, I listened to army veterans talk-ing about their stints in the Korean War.Usually after a beer or two, they’d turn theirconversation to the “outhouses” used by the

Koreans. They were amazed, even mystified, about the fact that theKoreans tried to lure passersby into their outhouses by making thetoilets especially attractive. The idea of someone wanting someoneelse’s crap always brought out a loud laugh from the vets.

Perhaps this attitude sums up the attitudes of Americans.Humanure is a waste product that we have to get rid of, and that’s allthere is to it. Only fools would think otherwise. One of the effects ofthis sort of attitude is that Americans don’t know and probably don’tcare where their humanure goes after it emerges from their rear endsas long as they don’t have to deal with it.

MEXICAN BIOLOGICAL DIGESTER

Well, where it goes depends on the type of “waste disposal sys-tem” used. Let’s start with the simplest: the Mexican biologicaldigester, also known as the stray dog. In India, this may be known asthe family pig. I spent a few months in southern Mexico in the late1970s in Quintana Roo on the Yucatan peninsula. There, toilets werenot available; people simply used the sand dunes along the coast. Noproblem, though. One of the small, unkempt and ubiquitous Mexicandogs would wait nearby with watering mouth until you did your

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84 The Humanure Handbook — Chapter 5: A Day in the Life of a Turd

PRIMITIVE BIOLOGICAL DIGESTER

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thing. Burying your excrement in that situation would have been anact of disrespect to the dog. No one wants sand in their food. A good,healthy, steaming turd at the crack of dawn on the Caribbean coastnever lasted more than 60 seconds before it became a hot meal for ahuman’s best friend. Yum.

THE OLD-FASHIONED OUTHOUSE

Next up the ladder of sophistication is the old-fashioned out-house, also known as the pit latrine. Simply stated, one digs a holeand defecates in it, and then does so again and again until the holefills up; then it’s covered with dirt. It’s nice to have a small buildingor “privy” over the hole to provide some privacy and shelter.However, the concept is simple: dig a hole and bury your excrement.Interestingly, this level of sophistication has not yet been surpassedin America. We still bury our excrement, in the form of sewagesludge, in landfill holes.

Outhouses create very real health, environmental and aesthet-ic problems. The hole in the ground is accessible to flies and mosqui-toes which can transmit diseases over a wide area. The pits leak pol-lutants into the ground even in dry soil. And the smell — hold your

SPREAD OF POLLUTION THROUGH WET SOIL BY OUTHOUSES

Source: Franceys, R. et al. (1992). A Guide to the Development

of On-Site Sanitation. p. 40. World Health Organization, Geneva.

15 m (50 feet)

POLLUTION

Direction of groundwater flow

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86 The Humanure Handbook — Chapter 5: A Day in the Life of a Turd

SPREAD OF POLLUTION THROUGH DRY SOIL BY OUTHOUSES

Source: Rybczynski, et al.

(1982). Appropriate

Technology for Water

Supply and Sanitation -

Low-Cost Technology

Options for Sanitation, A

State of the Art Review and

Annotated Bibliography.

World Bank. p. 52.

Outhouses will

transmit pollution

three meters (10

feet) vertically and

one meter (3 feet)

laterally, in dry soil.

pollution

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nose.Outhouses will transmit pollution three meters (10 feet)

below the outhouse hole and one meter (3 feet) sideways in dry soil.They can be expected to leak pollution 50 feet sideways in wet soils,following the direction of groundwater flow.

SEPTIC SYSTEMS

Another step up the ladder, one finds the septic tank, a com-mon method of human waste disposal in rural and suburban areas ofthe United States. In this system the turd is deposited into a contain-er of water, usually purified drinking water, and flushed away.

After the floating turd travels through a sewage pipe, it plopsinto a fairly large underground storage tank, or septic tank, usuallymade of concrete and sometimes of fiberglass. In Pennsylvania (U.S.),a 900 gallon tank is the minimum size allowed for a home with threeor fewer bedrooms.1 The heavier solids settle to the bottom of the tankand the liquids drain off into a leach field, which consists of an arrayof drain pipes situated below the ground surface allowing the liquidto seep out into the soil. The wastewater is expected to be undergoinganaerobic decomposition while in the tank. When septic tanks fill up,they are pumped out and the waste material is trucked to a sewagetreatment plant, although sometimes it’s illegally dumped.

SAND MOUNDS

In the event of poorly drained soil, either low-lying or with ahigh clay content, a standard leach field will not work very well, espe-cially when the ground is already saturated with rainwater or snowmelt. One can’t drain wastewater into soil that is already saturatedwith water. That’s when the sand mound sewage disposal system is

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SAND MOUND SYSTEM

Source: US EPA (1996). Wastewater Treatment:

Alternatives to Septic Systems (Guidance

Document) p. 8. EPA/909-K-96-001, June 1996.

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STANDARD SEPTIC TANK GRAVITY DISTRIBUTION SYSTEM

Source: US EPA (1987). It’s Your Choice — A Guidebook for Local Officials on Small Community WastewaterManagement Options, p. 40. EPA 430/9-87-006.

SEPTIC TANK

LEACH FIELD

CROSS-SECTION OF A SEPTIC TANKSource: Penn State College of Agriculture, Cooperative Extension, Agricultural Engineering Fact Sheet SW-165.

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employed. When the septic tank isn’t draining properly, a pump willkick in and pump the effluent into a pile of sand and gravel aboveground (although sometimes a pump isn’t necessary and gravity doesthe job). A perforated pipeline in the pile of sand allows the effluentto drain down through the mound. Sand mounds are usually coveredwith soil and grass. In Pennsylvania, sand mounds must be at leastone hundred feet downslope from a well or spring, fifty feet from astream, and five feet from a property line.2 According to local excavat-ing contractors, sand mounds cost $5,000 to $12,000 to construct inthe early 21st century. They must be built to exact government spec-ifications, and aren’t usable until they pass an official inspection.

GROUND WATER POLLUTION FROM SEPTIC SYSTEMS

Humans started disposing of “human waste”by defecating into a hole in the ground or an out-

house, then discovered we could float our turdsout to the hole using water and never have to

leave our shelter. However, one of theunfortunate problems with septic

systems is, like outhouses, theypollute our groundwater.

At the end of the 20th century,there were 22 million septic sys-tem sites in the United States,serving one fourth to one third of

the U.S. population. They werenotorious for leaching contami-

nants such as bacteria, viruses,nitrates, phosphates, chlorides and organic compounds such astrichloroethylene into the environment. An EPA study of chemicalsin septic tanks found toluene, methylene chloride, benzene, chloro-form and other volatile synthetic organic compounds related to homechemical use, many of them cancer-causing.3 Between 820 and 1,460billion gallons of this contaminated water were discharged per yearinto our shallowest aquifers.4 In the U.S., septic tanks are reported asa source of ground water contamination more than any other source.Forty-six states cite septic systems as sources of groundwater pollu-tion; nine of these reported them to be the primary source of ground-water contamination in their state.5

The word “septic” comes from the Greek “septikos” which

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means “to make putrid.” Today it still means “causing putrefaction,”putrefaction being “the decomposition of organic matter resulting inthe formation of foul-smelling products.” Septic systems are notdesigned to destroy human pathogens that may be in the humanwaste that enters the septic tank. Instead, septic systems are designedto collect human wastewater, settle out the solids, and anaerobicallydigest them to some extent, leaching the effluent into the ground.Therefore, septic systems can be highly pathogenic, allowing thetransmission of disease-causing bacteria, viruses, protozoa and intes-tinal parasites through the system.

One of the main concerns associated with septic systems isthe problem of human population density. Too many septic systemsin any given area will overload the soil’s natural purification systemsand allow large amounts of wastewater to contaminate the underlyingwatertable. A density of more than forty household septic systems persquare mile will cause an area to become a likely target for subsurfacecontamination, according to the EPA.6

Toxic chemicals are commonly released into the environmentfrom septic systems because people dump them down their drains.The chemicals are found in pesticides, paint, toilet cleaners, draincleaners, disinfectants, laundry solvents, antifreeze, rust proofers,septic tank and cesspool cleaners and many other cleaning solutions.In fact, over 400,000 gallons of septic tank cleaner liquids containingsynthetic organic chemicals were used in one year by the residents ofLong Island alone. Furthermore, some toxic chemicals can corrodepipes, thereby causing heavy metals to enter septic systems.7

In many cases, people who have septic tanks are forced to con-nect to sewage lines when the lines become available. A U.S. SupremeCourt case in 1992 reviewed a situation whereby town members inNew Hampshire had been forced to connect to a sewage line that sim-ply discharged untreated, raw sewage into the Connecticut River, andhad done so for 57 years. Despite the crude method of sewage dispos-al, state law required properties within 100 feet of the town sewer sys-tem to connect to it from the time it was built in 1932. This barbaricsewage disposal system apparently continued to operate until 1989,when state and federal sewage treatment laws forced a stop to thedumping of raw sewage into the river.8

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WASTEWATER TREATMENT PLANTS

There’s still another step up the ladder of wastewater treat-ment sophistication: the wastewater treatment plant, or sewage plant.The wastewater treatment plant is like a huge, very sophisticated sep-tic tank because it collects the waterborne excrement of large num-bers of humans. Inevitably, when one defecates or urinates into water,one pollutes the water. In order to avoid environmental pollution,that “wastewater” must somehow be rendered fit to return to theenvironment. The wastewater entering the treatment plant is 99%liquid because all sink water, bath water and everything else that goesdown one’s drain ends up at the plant too, which is why it’s called awater treatment plant. In some cases, storm water runoff also enterswastewater treatment plants via combined sewers. Industries, hospitals,gas stations and any place with a drain add to the contaminant blendin the wastewater stream.

Many modern wastewater plants use a process of activatedsludge treatment whereby oxygen is vigorously bubbled through thewastewater in order to activate microbial digestion of the solids. Thisaeration stage is combined with a settling stage that allows the solidsto be removed. The removed solids, known as sludge, are either usedto reinoculate the incoming wastewater, or they’re dewatered to theconsistency of a dry mud and buried in landfills. Sometimes thesludge is applied to agricultural land, and now, sometimes, it’s com-posted.

The microbes that digest the sludge consist of bacteria, fungi,protozoa, rotifers and nematodes.9 U.S. sewage treatment plants gen-erated about 7.6 million dry tons of sludge in 1989.10 New York Cityalone produces 143,810 dry tons of sludge every year.11 In 1993, theamount of sewage sludge produced annually in the U.S. was 110-150million wet metric tons. The water left behind is treated, usually withchlorine, and discharged into a stream, river or other body of water.Sewage treatment water releases to surface water in the United Statesin 1985 amounted to nearly 31 billion gallons per day.12 Incidentally, theamount of toilet paper used in 1991 to send all this waste to the sew-ers was 2.3 million tons.13 With each passing year, as the human pop-ulation increases, these figures go up.

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WASTE STABILIZATION PONDS

Perhaps one of the most ancient wastewater treatment meth-ods known to humans are waste stabilization ponds, also known asoxidation ponds or lagoons. They’re often found in small rural areaswhere land is available and cheap. Such ponds tend to be only a meterto a meter and a half deep, but vary in size and depth and can be threeor more meters deep.14 They utilize natural processes to “treat” wastematerials, relying on algae, bacteria and zooplankton to reduce theorganic content of the wastewater. A “healthy” lagoon will appeargreen in color because of the dense algae population. These lagoonsrequire about one acre for every 200 people served. Mechanically aer-ated lagoons only need 1/3 to 1/10 the land that unaerated stabiliza-tion ponds require. It’s a good idea to have several smaller lagoons inseries rather than one big one; normally, a minimum of three “cells”are used. Sludge collects in the bottom of the lagoons, and may haveto be removed every five or ten years and disposed of in an approvedmanner.15

CHLORINE

Wastewater leaving treatment plants is often treated withchlorine before being released into the environment. Therefore,besides contaminating water resources with feces, the act of defecat-ing into water often ultimately contributes to the contamination ofwater resources with chlorine.

Used since the early 1900s, chlorine is one of the most widelyproduced industrial chemicals. More than 10 million metric tons aremanufactured in the U.S. each year — $72 billion worth.16 Annually,approximately 5%, or 1.2 billion pounds of the chlorine manufac-tured is used for wastewater treatment and drinking water “purifica-tion.” The lethal liquid or green gas is mixed with the wastewaterfrom sewage treatment plants in order to kill disease-causingmicroorganisms before the water is discharged into streams, lakes,rivers and seas. It is also added to household drinking water viahousehold and municipal water treatment systems. Chlorine killsmicroorganisms by damaging their cell membranes, which leads to aleakage of their proteins, RNA, and DNA.17

Chlorine (Cl2) doesn’t exist in nature. It’s a potent poisonwhich reacts with water to produce a strongly oxidizing solution thatcan damage the moist tissue lining of the human respiratory tract.

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Ten to twenty parts per million (ppm) of chlorine gas in air rapidlyirritates the respiratory tract; even brief exposure at levels of 1,000ppm (one part in a thousand) can be fatal.18 Chlorine also kills fish,and reports of fish kills caused chlorine to come under the scrutiny ofscientists in the 1970s.

The fact that harmful compounds are formed as by-products ofchlorine use also raises concern. In 1976, the U.S. EnvironmentalProtection Agency reported that chlorine use not only poisoned fish,but could also cause the formation of cancer-causing compoundssuch as chloroform. Some known effects of chlorine-based pollutantson animal life include memory problems, stunted growth and cancerin humans; reproductive problems in minks and otters; reproductiveproblems, hatching problems and death in lake trout; and embryoabnormalities and death in snapping turtles.19

In a national study of 6,400 municipal wastewater treatmentplants, the EPA estimated that two thirds of them used too muchchlorine, exerting lethal effects at all levels of the aquatic food chain.Chlorine damages the gills of fish, inhibiting their ability to absorboxygen. It also can cause behavioral changes in fish, thereby affectingmigration and reproduction. Chlorine in streams can create chemical“dams” which prevent the free movement of some migratory fish.Fortunately, since 1984, there has been a 98% reduction in the use ofchlorine by sewage treatment plants, although chlorine use continuesto be a widespread problem because a lot of wastewater plants are stilldischarging it into small receiving waters.20

Another controversy associated with chlorine use involves“dioxin,” which is a common term for a large number of chlorinatedchemicals that are classified as possible human carcinogens by theEPA. It’s known that dioxins cause cancer in laboratory animals, buttheir effects on humans are still being debated. Dioxins, by-productsof the chemical manufacturing industry, are concentrated up throughthe food chain where they’re deposited in human fat tissues. A keyingredient in the formation of dioxin is chlorine, and indications arethat an increase in the use of chlorine results in a correspondingincrease in the dioxin content of the environment, even in areaswhere the only dioxin source is the atmosphere.21

In the upper atmosphere, chlorine molecules from air pollu-tion gobble up ozone; in the lower atmosphere, they bond with carbonto form organochlorines. Some of the 11,000 commercially usedorganochlorines include hazardous compounds such as DDT, PCBs,chloroform and carbon tetrachloride. Organochlorines rarely occur in

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nature, and living things have little defense against them. They’vebeen linked not only to cancer, but also to neurological damage,immune suppression and reproductive and developmental effects.When chlorine products are washed down the drain into a septictank, they’re producing organochlorines. Although compost microor-ganisms can degrade and make harmless many toxic chemicals, high-ly chlorinated compounds are disturbingly resistant to such biodegra-dation.22

“Any use of chlorine results in compounds that cause a wide rangeof ailments,” says Joe Thorton, a Greenpeace researcher, who adds,“Chlorine is simply not compatible with life. Once you create it, you can’tcontrol it.” 23

There’s no doubt that our nation’s sewage treatment systemsare polluting our drinking water sources with pathogens. As a result,chlorine is also being used to disinfect the water we drink as well as todisinfect discharges from wastewater treatment facilities. It is esti-mated that 79% of the U.S. population is exposed to chlorine.24

According to a 1992 study, chlorine is added to 75% of the nation’s drink-ing water and is linked to cancer. The results of the study suggestedthat at least 4,200 cases of bladder cancer and 6,500 cases of rectalcancer each year in the U.S. are associated with consumption of chlo-rinated drinking water.25 This association is strongest in people whohave been drinking chlorinated water for more than fifteen years.26

The U.S. Public Health Service reported that pregnantwomen who routinely drink or bathe in chlorinated tap water are at agreater risk of bearing premature or small babies, or babies with con-genital defects.27

According to a spokesperson for the chlorine industry, 87% ofwater systems in the U.S. use free chlorines; 11% use chloramines.Chloramines are a combination of chlorine and ammonia. The chlo-ramine treatment is becoming more widespread due to the healthconcerns over chlorine.28 However, EPA scientists admit that we’repretty ignorant about the potential by-products of the chloramineprocess, which involves ozonation of the water prior to the additionof chloramine.29

According to a U.S. General Accounting Office report in 1992,consumers are poorly informed about potentially serious violations ofdrinking water standards. In a review of twenty water systems in sixstates, out of 157 drinking water quality violations, the publicreceived a timely notice in only 17 of the cases.30

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ALTERNATIVE WASTEWATER TREATMENT SYSTEMS

New systems are being developed to purify wastewater. Onepopular experimental system today is the constructed, or artificial wet-lands system, which diverts wastewater through an aquatic environ-ment consisting of aquatic plants such as water hyacinths, bullrush-es, duckweed, lilies and cattails. The plants act as marsh filters, andthe microbes which thrive on their roots break down nitrogen andphosphorous compounds, as well as toxic chemicals. Although theydon’t break down heavy metals, the plants absorb them and they canthen be harvested for incineration or landfilled.31

According to EPA officials, the emergence of constructed wet-lands technology shows great potential as a cost-effective alternativeto wastewater treatment. The wetlands method is said to be relative-ly affordable, energy-efficient, practical and effective. The treatmentefficiency of properly constructed wetlands is said to compare wellwith conventional treatment systems.32 Unfortunately, wetlands sys-tems don’t recover the agricultural resources available in humanure.

Another system uses solar-powered, greenhouse-like technol-ogy to treat wastewater. This system uses hundreds of species of bac-teria, fungi, protozoa, snails, plants and fish, among other things, toproduce advanced levels of wastewater treatment. These SolarAquatics systems are also experimental, but appear hopeful.33 Again,the agricultural resources of humanure are lost when using any dis-posal method or wastewater treatment technique instead of a huma-nure recycling method.

When a household humanure recycling method is used, how-ever, and sewage is not being produced, most households will still beproducing graywater. Graywater is the water that is used for washing,bathing, and laundry, and it must be dealt with in a responsible man-ner before draining into the environment. Most households produce

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sewage (blackwater). Households which compost their humanuremay produce no sewage at all — these households are prime candi-dates for alternative graywater systems. Such systems are discussed inChapter 9.

AGRICULTURAL USE OF SEWAGE SLUDGE

Now here’s where a thoughtful person may ask, “Why not putsewage sludge back into the soil for agricultural purposes?”

One reason: government regulation. When I asked the super-visor of my local wastewater treatment plant if the one million gal-lons of sludge the plant produces each year, from a population of8,000 people, was being applied to agricultural land, he said, “It takessix months and five thousand dollars to get a permit for a land application.Another problem is that due to regulations, the sludge can’t lie on the sur-face after it’s applied, so it has to be plowed under shortly after application.When farmers get the right conditions to plow their fields, they plow them.They can’t wait around for us, and we can’t have sludge ready to go atplowing time.” It may be just as well.

Problems associated with the agricultural use of sewagesludge include groundwater, soil and crop contamination withpathogens, heavy metals, nitrates, and toxic and carcinogenic organ-ic compounds.34 Sewage sludge is a lot more than organic agricultur-al material. It can contain DDT, PCBs, mercury and other heavy met-als.35 One scientist alleges that more than 20 million gallons of usedmotor oil are dumped into sewers every year in the United States.36

America’s largest industrial facilities released over 550 mil-lion pounds of toxic pollutants into U.S. sewers in 1989 alone, accord-ing to the U.S. Public Interest Research Group. Between 1990 and1994, an additional 450 million pounds of toxic chemicals weredumped into sewage treatment systems, although the actual levels oftoxic discharges are said to be much higher than these.37

Of the top ten states responsible for toxic discharges to pub-lic sewers in 1991, Michigan took first prize with nearly 80 millionpounds, followed in order by New Jersey, Illinois, California, Texas,Virginia, Ohio, Tennessee, Wisconsin and Pennsylvania (around 20million pounds from PA).38

An interesting study on the agricultural use of sludge wasdone by a Mr. Purves in Scotland. He began applying sewage sludgeat the rate of 60 tons per acre to a plot of land in 1971. After fifteenyears of treating the soil with the sludge, he tested the vegetation

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grown on the plot for heavymetals. On finding that theheavy metals (lead, copper,nickel, zinc and cadmium)had been taken up by theplants, he concluded,“Contamination of soils with awide range of potentially toxicmetals following application ofsewage sludge is therefore virtu-ally irreversible.” 39 In otherwords, the heavy metals don’twash out of the soil, they enterthe food chain, and may con-taminate not only crops, butalso grazing animals.40

Other studies haveshown that heavy metals accu-mulate in the vegetable tissueof the plant to a much greaterextent than in the fruits, roots,or tubers. Therefore, if onemust grow food crops on soilfertilized with sewage sludgecontaminated with heavy met-als, one might be wise to pro-duce carrots or potatoes

instead of lettuce.41 Guinea pigs experimentally fed with swiss chardgrown on soil fertilized with sewage sludge showed no observable tox-icological effects. However, their adrenals showed elevated levels ofantimony, their kidneys had elevated levels of cadmium, there waselevated manganese in the liver and elevated tin in several other tis-sues.42

Estimated to contain 10 billion microorganisms per gram,sludge may contain many human pathogens.43 “The fact that sewagesludge contains a large population of fecal coliforms renders it suspect as apotential vector of bacterial pathogens and a possible contaminant of soil,water and air, not to mention crops. Numerous investigations in differentparts of the world have confirmed the presence of intestinal pathogenic bac-teria and animal parasites in sewage, sludge, and fecal materials.” 44

Because of their size and density, parasitic worm eggs settle

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BRAND NAMES OF SEWAGE SLUDGE

FERTILIZERS ONCE MARKETED

SOURCE CITY NAME*

Akron, OH . . . . . . . . .Akra-Soilite

Battle Creek, MI . . . .Battle Creek Plant Food

Boise, ID . . . . . . . . . .B.I. Organic

Charlotte, NC . . . . . .Humite & Turfood

Chicago, IL . . . . . . . .Chicagro & Nitroganic

Clearwater, FL . . . . . .Clear-O-Sludge

Fond du Lac, WI . . . .Fond du Green

Grand Rapids, MI . . .Rapidgro

Houston, TX . . . . . . .Hu-Actinite

Indianapolis, IN . . . . .Indas

Madison, WI . . . . . . .Nitrohumus

Massillon, OH . . . . . .Greengro

Milwaukee, WI . . . . . .Milorganite

Oshkosh, WI . . . . . . .Oshkonite

Pasadena, CA . . . . . .Nitroganic

Racine, WI . . . . . . . . .Ramos

Rockford, IL . . . . . . . .Nu-Vim

San Diego, CA . . . . .Nitro Gano

San Diego, CA . . . . .San-Diegonite

S. California . . . . . . . .Sludgeon

Schenectady, NY . . . .Orgro & Gro-hume

Toledo, OH . . . . . . . .Tol-e-gro

*Names are registered brand names.

Sources: Rodale, J. I. et al. (Eds.). (1960). The Complete Bookof Composting. Rodale Books Inc.: Emmaus, PA. pp. 789, 790.and Collins, Gilbeart H., (1955). Commercial Fertilizers - TheirSources and Use, Fifth Edition. McGraw-Hill Book Co., New York

Table 5.1

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into and concentrate in sewage sludge at wastewater treatment facili-ties. One study indicated that roundworm eggs could be recoveredfrom sludge at all stages of the wastewater treatment process, and thattwo-thirds of the samples examined had viable eggs.45 Agriculturaluse of the sludge can therefore infect soil with 6,000-12,000 viableparasitic worm eggs per square meter, per year. These eggs can per-sist in some soils for five years or more.46 Furthermore, Salmonellaebacteria in sewage sludge can remain viable on grassland for severalweeks, thereby making it necessary to restrict grazing on pasturelandafter a sludge application. Beef tapeworm (Taenia saginata), whichuses cattle as its intermediate host and humans as its final host, canalso infect cattle that graze on pastureland fertilized with sludge. Thetapeworm eggs can survive on sludged pasture for a full year.47

Another interesting study published in 1989 indicated thatbacteria surviving in sewage sludge show a high level of resistance toantibiotics, especially penicillin. Because heavy metals are concen-trated in sludge during the treatment process, the bacteria that sur-vive in the sludge can obviously resist heavy metal poisoning. Thesesame bacteria also show an inexplicable resistance to antibiotics, sug-gesting that somehow the resistance of the two environmental factorsare related in the bacterial strains that survive. The implication isthat sewage sludge selectively breeds antibiotic-resistant bacteria,which may enter the food chain if the agricultural use of the sludgebecomes widespread. The results of the study indicated that moreknowledge of antibiotic-resistant bacteria in sewage sludge should beacquired before sludge is disposed of on land.48

This poses somewhat of a problem. Collecting human excre-ment with wastewater and industrial pollutants seems to render theorganic refuse incapable of being adequately sanitized. It becomescontaminated enough to be unfit for agricultural purposes. As a con-sequence, sewage sludge is not highly sought after as a soil additive.For example, the state of Texas sued the U.S. EPA in July of 1992 forfailing to study environmental risks before approving the spreadingof sewage sludge in west Texas. Sludge was being spread on 128,000acres there by an Oklahoma firm, but the judge nevertheless refusedto issue an injunction to stop the spreading.49

Now that ocean dumping of sludge has been stopped, where’sit going to go? Researchers at Cornell University have suggested thatsewage sludge can be disposed of by surface applications in forests.Their studies suggest that brief and intermittent applications ofsludge to forestlands won’t adversely affect wildlife, despite the

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nitrates and heavy metals that are present in the sludge. They pointout that the need to find ways to get rid of sludge is compounded bythe fact that many landfills are expected to close and ocean dumpingis now banned.

Under the Cornell model, one dry ton of sludge could beapplied to an acre of forest each year.50 New York state alone produces370,000 tons of dry sludge per year, which would require 370,000acres of forest each year for sludge disposal. Consider the fact thatforty-nine other states produce 7.6 million dry tons of sludge. Thenthere’s figuring out how to get the sludge into the forests and how tospread it around. With all this in mind, a guy has to stop and wonder— the woods used to be the only place left to get away from it all!

The problem of treating and dumping sludge isn’t the onlyone. The costs of maintenance and upkeep of wastewater treatmentplants is another. According to a report issued by the EPA in 1992,U.S. cities and towns need as much as $110.6 billion over the nexttwenty years for enlarging, upgrading, and constructing wastewatertreatment facilities.51

Ironically, when sludge is composted, it may help to keep heavymetals out of the food chain. According to a 1992 report, compostedsludge lowered the uptake of lead in lettuce that had been deliberate-ly planted in lead-contaminated soil. The lettuce grown in the con-taminated soil which was amended with composted sludge had a 64%lower uptake of lead than lettuce planted in the same soil but withoutthe compost. The composted soil also lowered lead uptake in spinach,beets and carrots by more than 50%.52

Some scientists claim that the composting process transformsheavy metals into benign materials. One such scientist who designsfacilities that compost sewage sludge states, “At the final product stage,these [heavy] metals actually become beneficial micro-nutrients and traceminerals that add to the productivity of soil. This principle is now findingacceptance in the scientific community of the U.S.A. and is known as bio-logical transmutation, or also known as the Kervran-Effect.” Other scien-tists scoff at such a notion.

Composted sewage sludge that is microbiologically active canalso be used to detoxify areas contaminated with nuclear radiation oroil spills, according to researchers. Clearly, the composting of sewagesludge is a grossly underutilized alternative to landfill application,and it should be strongly promoted.53

Other scientists have shown that heavy metals in contaminat-ed compost are not biologically transmuted, but are actually concen-

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trated in the finished compost. This is most likely due to the fact thatthe compost mass shrinks considerably during the compostingprocess, showing reductions of 70%, while the amount of metalsremains the same. Some researchers have shown a decrease in theconcentrations of some heavy metals and an increase in the concentra-tions of others, for reasons that are unclear. Others show a consider-able decrease in the concentrations of heavy metals between thesludge and the finished compost. Results from various researchers“are giving a confusing idea about the behavior of heavy metals during com-posting. No common pattern of behavior can be drawn between similarmaterials and the same metals . . .” 54 However, metals concentrations infinished compost seem to be low enough that they are not consideredto be a problem largely because metal-contaminated sludge is greatlydiluted by other clean organic materials when composted.55

GLOBAL SEWERS AND PET TURDS

Let’s assume that the whole world adopted the sewage philos-ophy we have in the United States: defecate into water and then treatthe polluted water. What would that scenario be like? Well, for onething it wouldn’t work. It takes between 1,000 and 2,000 tons of waterat various stages in the process to flush one ton of humanure. In aworld of just six billion people producing a conservative estimate of1.2 million metric tons of human excrement daily, the amount ofwater required to flush it all would not be obtainable.56 Consideringthe increasing landfill space that would be needed to dispose of theincreasing amounts of sewage sludge, and the tons of toxic chemicalsrequired to “sterilize” the wastewater, one can realize that this systemof human waste disposal is far from sustainable and cannot serve theneeds of humanity in the long term.

According to Barbara Ward, President of the InternationalInstitute for Environment and Development, “Conventional ‘Western’methods of waterborne sewerage are simply beyond the reach of most [of theworld’s] communities.They are far too expensive. And they often demand alevel of water use that local water resources cannot supply. If Western stan-dards were made the norm, some $200 billion alone [early 1980s] wouldhave to be invested in sewerage to achieve the target of basic sanitation forall. Resources on this scale are simply not in sight.”

To quote Lattee Fahm, “In today’s world [1980], some 4.5 billionpeople produce excretal matters at about 5.5 million metric tons every twen-ty-four hours, close to two billion metric tons per year. [Humanity] now

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occupies a time/growth dimension in which the world population doubles inthirty five years or less. In this new universe, there is only one viable andecologically consistent solution to the body waste problems — the processingand application of [humanure] for its agronutrient content.” 57 This senti-ment is echoed by World Bank researchers, who state, “[I]t can be esti-mated that the backlog of over one billion people not now provided withwater or sanitation service will grow, not decrease. It has also been estimat-ed that most developing economies will be unable to finance water carriagewaste disposal systems even if loan funds were available.” 58

In other words, we have to understand that humanure is anatural substance, produced by a process vital to life (human diges-tion), originating from the earth in the form of food, and valuable asan organic refuse material that can be returned to the earth in orderto produce more food for humans. That’s where composting comes in.

But hey, wait, let’s not rush to judgement. We forgot aboutincinerating our excrements. We can dry our turds out, then truckthem to big incinerators and burn the hell out of them. That way,instead of having fecal pollution in our drinking water or forests, wecan breathe it in our air. Unfortunately, burning sludge with othermunicipal waste produces emissions of particulate matter, sulfurdioxide, nitrogen oxides, carbon monoxide, lead, volatile hydrocar-bons, acid gases, trace organic compounds and trace metals. The left-over ash has a high concentration of heavy metals, such as cadmiumand lead.59 Doesn’t sound so good if you live downwind, does it?

How about microwaving it? Don’t laugh, someone’s alreadyinvented the microwave toilet.60 This just might be a good cure forhemorrhoids, too. But heck, let’s get serious and shoot it into outerspace. Why not? It probably wouldn’t cost too much per turd afterwe’ve dried the stuff out. This could add a new meaning to the phrase“the Captain’s log.” Beam up another one, Scotty!

Better yet, we can dry our turds out, chlorinate them, getsomeone in Taiwan to make little plastic sunglasses for them, thenwe’ll sell them as Pet Turds! Now that’s an entrepreneurial solution,isn’t it? Any volunteer investors out there?

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